1//===-- ValueEnumerator.cpp - Number values and types for bitcode writer --===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements the ValueEnumerator class. 11// 12//===----------------------------------------------------------------------===// 13 14#include "ValueEnumerator.h" 15#include "llvm/ADT/STLExtras.h" 16#include "llvm/ADT/SmallPtrSet.h" 17#include "llvm/IR/Constants.h" 18#include "llvm/IR/DerivedTypes.h" 19#include "llvm/IR/Instructions.h" 20#include "llvm/IR/Module.h" 21#include "llvm/IR/ValueSymbolTable.h" 22#include "llvm/Support/Debug.h" 23#include "llvm/Support/raw_ostream.h" 24#include <algorithm> 25using namespace llvm; 26 27static bool isIntOrIntVectorValue(const std::pair<const Value*, unsigned> &V) { 28 return V.first->getType()->isIntOrIntVectorTy(); 29} 30 31/// ValueEnumerator - Enumerate module-level information. 32ValueEnumerator::ValueEnumerator(const Module *M) { 33 // Enumerate the global variables. 34 for (Module::const_global_iterator I = M->global_begin(), 35 E = M->global_end(); I != E; ++I) 36 EnumerateValue(I); 37 38 // Enumerate the functions. 39 for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) { 40 EnumerateValue(I); 41 EnumerateAttributes(cast<Function>(I)->getAttributes()); 42 } 43 44 // Enumerate the aliases. 45 for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end(); 46 I != E; ++I) 47 EnumerateValue(I); 48 49 // Remember what is the cutoff between globalvalue's and other constants. 50 unsigned FirstConstant = Values.size(); 51 52 // Enumerate the global variable initializers. 53 for (Module::const_global_iterator I = M->global_begin(), 54 E = M->global_end(); I != E; ++I) 55 if (I->hasInitializer()) 56 EnumerateValue(I->getInitializer()); 57 58 // Enumerate the aliasees. 59 for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end(); 60 I != E; ++I) 61 EnumerateValue(I->getAliasee()); 62 63 // Enumerate the prefix data constants. 64 for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) 65 if (I->hasPrefixData()) 66 EnumerateValue(I->getPrefixData()); 67 68 // Insert constants and metadata that are named at module level into the slot 69 // pool so that the module symbol table can refer to them... 70 EnumerateValueSymbolTable(M->getValueSymbolTable()); 71 EnumerateNamedMetadata(M); 72 73 SmallVector<std::pair<unsigned, MDNode*>, 8> MDs; 74 75 // Enumerate types used by function bodies and argument lists. 76 for (const Function &F : *M) { 77 for (const Argument &A : F.args()) 78 EnumerateType(A.getType()); 79 80 for (const BasicBlock &BB : F) 81 for (const Instruction &I : BB) { 82 for (const Use &Op : I.operands()) { 83 if (MDNode *MD = dyn_cast<MDNode>(&Op)) 84 if (MD->isFunctionLocal() && MD->getFunction()) 85 // These will get enumerated during function-incorporation. 86 continue; 87 EnumerateOperandType(Op); 88 } 89 EnumerateType(I.getType()); 90 if (const CallInst *CI = dyn_cast<CallInst>(&I)) 91 EnumerateAttributes(CI->getAttributes()); 92 else if (const InvokeInst *II = dyn_cast<InvokeInst>(&I)) 93 EnumerateAttributes(II->getAttributes()); 94 95 // Enumerate metadata attached with this instruction. 96 MDs.clear(); 97 I.getAllMetadataOtherThanDebugLoc(MDs); 98 for (unsigned i = 0, e = MDs.size(); i != e; ++i) 99 EnumerateMetadata(MDs[i].second); 100 101 if (!I.getDebugLoc().isUnknown()) { 102 MDNode *Scope, *IA; 103 I.getDebugLoc().getScopeAndInlinedAt(Scope, IA, I.getContext()); 104 if (Scope) EnumerateMetadata(Scope); 105 if (IA) EnumerateMetadata(IA); 106 } 107 } 108 } 109 110 // Optimize constant ordering. 111 OptimizeConstants(FirstConstant, Values.size()); 112} 113 114unsigned ValueEnumerator::getInstructionID(const Instruction *Inst) const { 115 InstructionMapType::const_iterator I = InstructionMap.find(Inst); 116 assert(I != InstructionMap.end() && "Instruction is not mapped!"); 117 return I->second; 118} 119 120unsigned ValueEnumerator::getComdatID(const Comdat *C) const { 121 unsigned ComdatID = Comdats.idFor(C); 122 assert(ComdatID && "Comdat not found!"); 123 return ComdatID; 124} 125 126void ValueEnumerator::setInstructionID(const Instruction *I) { 127 InstructionMap[I] = InstructionCount++; 128} 129 130unsigned ValueEnumerator::getValueID(const Value *V) const { 131 if (isa<MDNode>(V) || isa<MDString>(V)) { 132 ValueMapType::const_iterator I = MDValueMap.find(V); 133 assert(I != MDValueMap.end() && "Value not in slotcalculator!"); 134 return I->second-1; 135 } 136 137 ValueMapType::const_iterator I = ValueMap.find(V); 138 assert(I != ValueMap.end() && "Value not in slotcalculator!"); 139 return I->second-1; 140} 141 142void ValueEnumerator::dump() const { 143 print(dbgs(), ValueMap, "Default"); 144 dbgs() << '\n'; 145 print(dbgs(), MDValueMap, "MetaData"); 146 dbgs() << '\n'; 147} 148 149void ValueEnumerator::print(raw_ostream &OS, const ValueMapType &Map, 150 const char *Name) const { 151 152 OS << "Map Name: " << Name << "\n"; 153 OS << "Size: " << Map.size() << "\n"; 154 for (ValueMapType::const_iterator I = Map.begin(), 155 E = Map.end(); I != E; ++I) { 156 157 const Value *V = I->first; 158 if (V->hasName()) 159 OS << "Value: " << V->getName(); 160 else 161 OS << "Value: [null]\n"; 162 V->dump(); 163 164 OS << " Uses(" << std::distance(V->use_begin(),V->use_end()) << "):"; 165 for (const Use &U : V->uses()) { 166 if (&U != &*V->use_begin()) 167 OS << ","; 168 if(U->hasName()) 169 OS << " " << U->getName(); 170 else 171 OS << " [null]"; 172 173 } 174 OS << "\n\n"; 175 } 176} 177 178/// OptimizeConstants - Reorder constant pool for denser encoding. 179void ValueEnumerator::OptimizeConstants(unsigned CstStart, unsigned CstEnd) { 180 if (CstStart == CstEnd || CstStart+1 == CstEnd) return; 181 182 std::stable_sort(Values.begin() + CstStart, Values.begin() + CstEnd, 183 [this](const std::pair<const Value *, unsigned> &LHS, 184 const std::pair<const Value *, unsigned> &RHS) { 185 // Sort by plane. 186 if (LHS.first->getType() != RHS.first->getType()) 187 return getTypeID(LHS.first->getType()) < getTypeID(RHS.first->getType()); 188 // Then by frequency. 189 return LHS.second > RHS.second; 190 }); 191 192 // Ensure that integer and vector of integer constants are at the start of the 193 // constant pool. This is important so that GEP structure indices come before 194 // gep constant exprs. 195 std::partition(Values.begin()+CstStart, Values.begin()+CstEnd, 196 isIntOrIntVectorValue); 197 198 // Rebuild the modified portion of ValueMap. 199 for (; CstStart != CstEnd; ++CstStart) 200 ValueMap[Values[CstStart].first] = CstStart+1; 201} 202 203 204/// EnumerateValueSymbolTable - Insert all of the values in the specified symbol 205/// table into the values table. 206void ValueEnumerator::EnumerateValueSymbolTable(const ValueSymbolTable &VST) { 207 for (ValueSymbolTable::const_iterator VI = VST.begin(), VE = VST.end(); 208 VI != VE; ++VI) 209 EnumerateValue(VI->getValue()); 210} 211 212/// EnumerateNamedMetadata - Insert all of the values referenced by 213/// named metadata in the specified module. 214void ValueEnumerator::EnumerateNamedMetadata(const Module *M) { 215 for (Module::const_named_metadata_iterator I = M->named_metadata_begin(), 216 E = M->named_metadata_end(); I != E; ++I) 217 EnumerateNamedMDNode(I); 218} 219 220void ValueEnumerator::EnumerateNamedMDNode(const NamedMDNode *MD) { 221 for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i) 222 EnumerateMetadata(MD->getOperand(i)); 223} 224 225/// EnumerateMDNodeOperands - Enumerate all non-function-local values 226/// and types referenced by the given MDNode. 227void ValueEnumerator::EnumerateMDNodeOperands(const MDNode *N) { 228 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) { 229 if (Value *V = N->getOperand(i)) { 230 if (isa<MDNode>(V) || isa<MDString>(V)) 231 EnumerateMetadata(V); 232 else if (!isa<Instruction>(V) && !isa<Argument>(V)) 233 EnumerateValue(V); 234 } else 235 EnumerateType(Type::getVoidTy(N->getContext())); 236 } 237} 238 239void ValueEnumerator::EnumerateMetadata(const Value *MD) { 240 assert((isa<MDNode>(MD) || isa<MDString>(MD)) && "Invalid metadata kind"); 241 242 // Enumerate the type of this value. 243 EnumerateType(MD->getType()); 244 245 const MDNode *N = dyn_cast<MDNode>(MD); 246 247 // In the module-level pass, skip function-local nodes themselves, but 248 // do walk their operands. 249 if (N && N->isFunctionLocal() && N->getFunction()) { 250 EnumerateMDNodeOperands(N); 251 return; 252 } 253 254 // Check to see if it's already in! 255 unsigned &MDValueID = MDValueMap[MD]; 256 if (MDValueID) { 257 // Increment use count. 258 MDValues[MDValueID-1].second++; 259 return; 260 } 261 MDValues.push_back(std::make_pair(MD, 1U)); 262 MDValueID = MDValues.size(); 263 264 // Enumerate all non-function-local operands. 265 if (N) 266 EnumerateMDNodeOperands(N); 267} 268 269/// EnumerateFunctionLocalMetadataa - Incorporate function-local metadata 270/// information reachable from the given MDNode. 271void ValueEnumerator::EnumerateFunctionLocalMetadata(const MDNode *N) { 272 assert(N->isFunctionLocal() && N->getFunction() && 273 "EnumerateFunctionLocalMetadata called on non-function-local mdnode!"); 274 275 // Enumerate the type of this value. 276 EnumerateType(N->getType()); 277 278 // Check to see if it's already in! 279 unsigned &MDValueID = MDValueMap[N]; 280 if (MDValueID) { 281 // Increment use count. 282 MDValues[MDValueID-1].second++; 283 return; 284 } 285 MDValues.push_back(std::make_pair(N, 1U)); 286 MDValueID = MDValues.size(); 287 288 // To incoroporate function-local information visit all function-local 289 // MDNodes and all function-local values they reference. 290 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) 291 if (Value *V = N->getOperand(i)) { 292 if (MDNode *O = dyn_cast<MDNode>(V)) { 293 if (O->isFunctionLocal() && O->getFunction()) 294 EnumerateFunctionLocalMetadata(O); 295 } else if (isa<Instruction>(V) || isa<Argument>(V)) 296 EnumerateValue(V); 297 } 298 299 // Also, collect all function-local MDNodes for easy access. 300 FunctionLocalMDs.push_back(N); 301} 302 303void ValueEnumerator::EnumerateValue(const Value *V) { 304 assert(!V->getType()->isVoidTy() && "Can't insert void values!"); 305 assert(!isa<MDNode>(V) && !isa<MDString>(V) && 306 "EnumerateValue doesn't handle Metadata!"); 307 308 // Check to see if it's already in! 309 unsigned &ValueID = ValueMap[V]; 310 if (ValueID) { 311 // Increment use count. 312 Values[ValueID-1].second++; 313 return; 314 } 315 316 if (auto *GO = dyn_cast<GlobalObject>(V)) 317 if (const Comdat *C = GO->getComdat()) 318 Comdats.insert(C); 319 320 // Enumerate the type of this value. 321 EnumerateType(V->getType()); 322 323 if (const Constant *C = dyn_cast<Constant>(V)) { 324 if (isa<GlobalValue>(C)) { 325 // Initializers for globals are handled explicitly elsewhere. 326 } else if (C->getNumOperands()) { 327 // If a constant has operands, enumerate them. This makes sure that if a 328 // constant has uses (for example an array of const ints), that they are 329 // inserted also. 330 331 // We prefer to enumerate them with values before we enumerate the user 332 // itself. This makes it more likely that we can avoid forward references 333 // in the reader. We know that there can be no cycles in the constants 334 // graph that don't go through a global variable. 335 for (User::const_op_iterator I = C->op_begin(), E = C->op_end(); 336 I != E; ++I) 337 if (!isa<BasicBlock>(*I)) // Don't enumerate BB operand to BlockAddress. 338 EnumerateValue(*I); 339 340 // Finally, add the value. Doing this could make the ValueID reference be 341 // dangling, don't reuse it. 342 Values.push_back(std::make_pair(V, 1U)); 343 ValueMap[V] = Values.size(); 344 return; 345 } 346 } 347 348 // Add the value. 349 Values.push_back(std::make_pair(V, 1U)); 350 ValueID = Values.size(); 351} 352 353 354void ValueEnumerator::EnumerateType(Type *Ty) { 355 unsigned *TypeID = &TypeMap[Ty]; 356 357 // We've already seen this type. 358 if (*TypeID) 359 return; 360 361 // If it is a non-anonymous struct, mark the type as being visited so that we 362 // don't recursively visit it. This is safe because we allow forward 363 // references of these in the bitcode reader. 364 if (StructType *STy = dyn_cast<StructType>(Ty)) 365 if (!STy->isLiteral()) 366 *TypeID = ~0U; 367 368 // Enumerate all of the subtypes before we enumerate this type. This ensures 369 // that the type will be enumerated in an order that can be directly built. 370 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); 371 I != E; ++I) 372 EnumerateType(*I); 373 374 // Refresh the TypeID pointer in case the table rehashed. 375 TypeID = &TypeMap[Ty]; 376 377 // Check to see if we got the pointer another way. This can happen when 378 // enumerating recursive types that hit the base case deeper than they start. 379 // 380 // If this is actually a struct that we are treating as forward ref'able, 381 // then emit the definition now that all of its contents are available. 382 if (*TypeID && *TypeID != ~0U) 383 return; 384 385 // Add this type now that its contents are all happily enumerated. 386 Types.push_back(Ty); 387 388 *TypeID = Types.size(); 389} 390 391// Enumerate the types for the specified value. If the value is a constant, 392// walk through it, enumerating the types of the constant. 393void ValueEnumerator::EnumerateOperandType(const Value *V) { 394 EnumerateType(V->getType()); 395 396 if (const Constant *C = dyn_cast<Constant>(V)) { 397 // If this constant is already enumerated, ignore it, we know its type must 398 // be enumerated. 399 if (ValueMap.count(V)) return; 400 401 // This constant may have operands, make sure to enumerate the types in 402 // them. 403 for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i) { 404 const Value *Op = C->getOperand(i); 405 406 // Don't enumerate basic blocks here, this happens as operands to 407 // blockaddress. 408 if (isa<BasicBlock>(Op)) continue; 409 410 EnumerateOperandType(Op); 411 } 412 413 if (const MDNode *N = dyn_cast<MDNode>(V)) { 414 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) 415 if (Value *Elem = N->getOperand(i)) 416 EnumerateOperandType(Elem); 417 } 418 } else if (isa<MDString>(V) || isa<MDNode>(V)) 419 EnumerateMetadata(V); 420} 421 422void ValueEnumerator::EnumerateAttributes(AttributeSet PAL) { 423 if (PAL.isEmpty()) return; // null is always 0. 424 425 // Do a lookup. 426 unsigned &Entry = AttributeMap[PAL]; 427 if (Entry == 0) { 428 // Never saw this before, add it. 429 Attribute.push_back(PAL); 430 Entry = Attribute.size(); 431 } 432 433 // Do lookups for all attribute groups. 434 for (unsigned i = 0, e = PAL.getNumSlots(); i != e; ++i) { 435 AttributeSet AS = PAL.getSlotAttributes(i); 436 unsigned &Entry = AttributeGroupMap[AS]; 437 if (Entry == 0) { 438 AttributeGroups.push_back(AS); 439 Entry = AttributeGroups.size(); 440 } 441 } 442} 443 444void ValueEnumerator::incorporateFunction(const Function &F) { 445 InstructionCount = 0; 446 NumModuleValues = Values.size(); 447 NumModuleMDValues = MDValues.size(); 448 449 // Adding function arguments to the value table. 450 for (Function::const_arg_iterator I = F.arg_begin(), E = F.arg_end(); 451 I != E; ++I) 452 EnumerateValue(I); 453 454 FirstFuncConstantID = Values.size(); 455 456 // Add all function-level constants to the value table. 457 for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB) { 458 for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I) 459 for (User::const_op_iterator OI = I->op_begin(), E = I->op_end(); 460 OI != E; ++OI) { 461 if ((isa<Constant>(*OI) && !isa<GlobalValue>(*OI)) || 462 isa<InlineAsm>(*OI)) 463 EnumerateValue(*OI); 464 } 465 BasicBlocks.push_back(BB); 466 ValueMap[BB] = BasicBlocks.size(); 467 } 468 469 // Optimize the constant layout. 470 OptimizeConstants(FirstFuncConstantID, Values.size()); 471 472 // Add the function's parameter attributes so they are available for use in 473 // the function's instruction. 474 EnumerateAttributes(F.getAttributes()); 475 476 FirstInstID = Values.size(); 477 478 SmallVector<MDNode *, 8> FnLocalMDVector; 479 // Add all of the instructions. 480 for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB) { 481 for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I) { 482 for (User::const_op_iterator OI = I->op_begin(), E = I->op_end(); 483 OI != E; ++OI) { 484 if (MDNode *MD = dyn_cast<MDNode>(*OI)) 485 if (MD->isFunctionLocal() && MD->getFunction()) 486 // Enumerate metadata after the instructions they might refer to. 487 FnLocalMDVector.push_back(MD); 488 } 489 490 SmallVector<std::pair<unsigned, MDNode*>, 8> MDs; 491 I->getAllMetadataOtherThanDebugLoc(MDs); 492 for (unsigned i = 0, e = MDs.size(); i != e; ++i) { 493 MDNode *N = MDs[i].second; 494 if (N->isFunctionLocal() && N->getFunction()) 495 FnLocalMDVector.push_back(N); 496 } 497 498 if (!I->getType()->isVoidTy()) 499 EnumerateValue(I); 500 } 501 } 502 503 // Add all of the function-local metadata. 504 for (unsigned i = 0, e = FnLocalMDVector.size(); i != e; ++i) 505 EnumerateFunctionLocalMetadata(FnLocalMDVector[i]); 506} 507 508void ValueEnumerator::purgeFunction() { 509 /// Remove purged values from the ValueMap. 510 for (unsigned i = NumModuleValues, e = Values.size(); i != e; ++i) 511 ValueMap.erase(Values[i].first); 512 for (unsigned i = NumModuleMDValues, e = MDValues.size(); i != e; ++i) 513 MDValueMap.erase(MDValues[i].first); 514 for (unsigned i = 0, e = BasicBlocks.size(); i != e; ++i) 515 ValueMap.erase(BasicBlocks[i]); 516 517 Values.resize(NumModuleValues); 518 MDValues.resize(NumModuleMDValues); 519 BasicBlocks.clear(); 520 FunctionLocalMDs.clear(); 521} 522 523static void IncorporateFunctionInfoGlobalBBIDs(const Function *F, 524 DenseMap<const BasicBlock*, unsigned> &IDMap) { 525 unsigned Counter = 0; 526 for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB) 527 IDMap[BB] = ++Counter; 528} 529 530/// getGlobalBasicBlockID - This returns the function-specific ID for the 531/// specified basic block. This is relatively expensive information, so it 532/// should only be used by rare constructs such as address-of-label. 533unsigned ValueEnumerator::getGlobalBasicBlockID(const BasicBlock *BB) const { 534 unsigned &Idx = GlobalBasicBlockIDs[BB]; 535 if (Idx != 0) 536 return Idx-1; 537 538 IncorporateFunctionInfoGlobalBBIDs(BB->getParent(), GlobalBasicBlockIDs); 539 return getGlobalBasicBlockID(BB); 540} 541 542